The Family Smoking Prevention and Tobacco Control Act (TCA; 2009) gave the FDA authority to regulate how tobacco products are advertised. Ongoing legal challenges by the tobacco industry make it difficult to know precisely what kinds of tobacco advertising and marketing regulations will ultimately be permitted. The success of overcoming legal challenges and implementing any TCA-driven advertising regulations is dependent, in part, on the extent to which a given regulatory approach is supported by a strong evidence base. One of the thorniest issues in this regard is how to best regulate retail Point-of-Sale (POS) tobacco advertising. POS advertising includes indoor and outdoor billboard advertising, and prominent, expansive displays of many different types of tobacco products at the POS location (i.e., the tobacco power wall display). The TCA offers broad guidance for states and local communities to regulate the time, place, and manner of advertising at POS, but there is little specific information available as to how to regulate the POS environment to most effectively reduce its effects on adolescent smoking. The overall aim of this research is to experimentally evaluate the extent to which the location of tobacco power wall displays (Study 1) and inclusion of anti-tobacco messages at POS (Study 2) influence tobacco use risk in a middle and high school students (ages 11-17). As part of this project, we will construct an experimental POS convenience store that sells tobacco products in addition to other products typically found in such stores (e.g., soda, water, candy, etc.). This experimental POS retail store, or store lab, will allow us to manipulate key ingredients of the POS retail environment, including placement of tobacco power wall displays and presence of anti-tobacco posters, in a highly controlled, but externally and ecologically valid way. In both studies, participants will enter the store lab and spend 4 minutes picking out and purchasing $5 worth of (non-tobacco) products in the store. After exiting the store, they will complete items that tap into their tobacco use risk (cigarette smoking risk and smokeless tobacco risk). Study 1 will evaluate the effects of tobacco power wall display location on tobacco use risk by manipulating power wall display location within the POS environment in a between subjects design. The locations that will be compared are: behind the cashier (cashier); side-wall display, away from cashier (side-wall); and display hidden from view (hidden). Study 2 will examine the effects of including anti-tobacco use posters in the POS environment to examine their effects on tobacco use risk in a between subjects design. The anti-tobacco poster conditions that will be compared are: no poster (none); a small poster at the cash register (cash register); a large poster on the tobacco power wall display (power wall); and posters at the cash register and on the power wall (combined). We will also examine psychosocial mediators of any observed experimental effects of store lab structure on tobacco use risk. Advancing an understanding of how to best reduce the effect of tobacco wall displays at POS will inform regulatory science designed to reduce adolescent tobacco use.